The present invention relates to a releasing lubricant for use in forging and extrusion processes having excellent releasing characteristics.
As releasing lubricants for use in forging and extrusion processes, there have been known mineral oil, a mixture of mineral oil with graphite and a mixture of graphite with water.
However, mineral oil has not only insufficient lubricating and releasing properties but also environmental and operational problems when used in a hot working, such as smoking, dust generation and fire hazard.
Graphite mixtures have lubricating and releasing properties superior to those of mineral oil but the above-mentioned environmental and operational problems have not yet been solved or overcome.
Further, there has been proposed a lubricant comprising a water-soluble glass containing P.sub.2 O.sub.5, B.sub.2 O.sub.3 and M.sub.2 O (M being an alkali metal) and a phyllosilicate such as mica.
However, this lubricant has a defect that when it is put to use where great emphasis is laid on one of the lubricating and releasing properties at the sacrifice of the other property, either the releasing or the lubricating property becomes insufficient and, in an extreme case, seizure is caused, since the lubricant is intended to exhibit well-balanced lubricating and releasing properties in the forging or extrusion process.